Symmetry and similarity effects in the comparison of visual patterns

Abstract

Models to explain same-different RT disparity have variously emphasized encoding or comparison processes. Of the latter, a dual-process holistic-analytic model that bears a similarity to a putative distinction between hemispheric processes has been proposed. Here two experiments test the models by employing simultaneous and successive matching while varying letter similarity, symmetry, and visual field of presentation. Same-different disparity is found regardless of delay, although it can be eliminated with appropriate similarity and symmetry manipulations. While visual field interacts with the same-different factor, it fails to do so in a manner consistent with the proposed hemispheric dichotomy. These and other results argue against encoding models of letter matching, and support a revised visual comparison model that incorporates dual processing and response criterion elements. However, the role of lateralized processes remains unclear. © 1983 Psychonomic Society, Inc.